U.S. patent number 10,440,021 [Application Number 15/358,283] was granted by the patent office on 2019-10-08 for authentication method, authentication system, and controller.
This patent grant is currently assigned to PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.. The grantee listed for this patent is Panasonic Intellectual Property Management Co., Ltd.. Invention is credited to Manabu Maeda, Yoichi Masuda, Hideki Matsushima, Tomoki Takazoe, Yuji Unagami.
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United States Patent |
10,440,021 |
Unagami , et al. |
October 8, 2019 |
Authentication method, authentication system, and controller
Abstract
A first controller generates a first group key, executes first
mutual authentication with devices within a group, and shares a
first group key with devices that have succeeded in authentication.
At least one controller within the group decides a coordinator that
manages a group key used in common in the group, from controllers
including a second controller newly joined in the group. The first
controller executes second mutual authentication with the
coordinator, and shares the first group key with the coordinator.
The coordinator performs encrypted communication within the group
using the first group key. The coordinator generates a second group
key when valid time of the first group key is equal to or smaller
than a predetermined value, executes third mutual authentication
with the devices and controllers within the group, and updates the
group key of the devices and controllers that have succeeded in
authentication to the second group key.
Inventors: |
Unagami; Yuji (Osaka,
JP), Maeda; Manabu (Osaka, JP), Takazoe;
Tomoki (Kanagawa, JP), Masuda; Yoichi (Tokyo,
JP), Matsushima; Hideki (Osaka, JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
Panasonic Intellectual Property Management Co., Ltd. |
Osaka |
N/A |
JP |
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Assignee: |
PANASONIC INTELLECTUAL PROPERTY
MANAGEMENT CO., LTD. (Osaka, JP)
|
Family
ID: |
54833156 |
Appl.
No.: |
15/358,283 |
Filed: |
November 22, 2016 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20170078283 A1 |
Mar 16, 2017 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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PCT/JP2015/002525 |
May 20, 2015 |
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62010181 |
Jun 10, 2014 |
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62009984 |
Jun 10, 2014 |
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Foreign Application Priority Data
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Mar 24, 2015 [JP] |
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2015-060813 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04L
63/065 (20130101); G06F 21/445 (20130101); H04L
9/0833 (20130101); H04L 63/104 (20130101); H04L
9/0891 (20130101); H04L 9/3263 (20130101); H04L
63/0869 (20130101); H04L 9/3273 (20130101); H04L
9/14 (20130101); H04L 9/0844 (20130101); H04L
9/30 (20130101) |
Current International
Class: |
H04L
9/00 (20060101); H04L 9/08 (20060101); G06F
21/44 (20130101); H04L 9/32 (20060101); H04L
9/30 (20060101); H04L 29/06 (20060101); H04L
9/14 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1624628 |
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Feb 2006 |
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EP |
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2004-133576 |
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Apr 2004 |
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JP |
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2005-341528 |
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Dec 2005 |
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JP |
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2006-526933 |
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Nov 2006 |
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JP |
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2010-245847 |
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Oct 2010 |
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JP |
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2013-207496 |
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Oct 2013 |
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JP |
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2013-240021 |
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Nov 2013 |
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JP |
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Other References
International Search Report of PCT application No.
PCT/JP2015/002525 dated Jul. 28, 2015. cited by applicant .
Federal Information Processing Standards Publication(FIPS
PUB)186-4: "Digital Signature Standard(DSS)" National Institute of
Standards and Technology(NIST), Jul. 2013. cited by applicant .
NIST Special Publication 800-56A Revision 2: "Recommendation for
Pair-Wise Key Establishment Schemes Using Discrete Logarithm
Cryptography", National Institute of Standards and Technology
(NIST), May 2013. cited by applicant .
IETF: RFC5191: "Protocol for Carrying Authentication for Network
Access (PANA)", Internet Engineering Task Force (IETF), May 2008.
cited by applicant .
IETF: RFC6347: "Datagram Transport Layer Security Version 1.2",
Internet Engineering Task Force (IETF), Jan. 2012. cited by
applicant .
The Extended European Search Report, dated Apr. 20, 2017, by the
European Patent Office (EPO) for the related European Patent
Application No. 15807040.9. cited by applicant.
|
Primary Examiner: Jeudy; Josnel
Attorney, Agent or Firm: Greenblum & Bernstein,
P.L.C.
Claims
What is claimed is:
1. An authentication method for a group to which one or more
devices and one or more controllers, including a first controller
on a network, belong, the authentication method comprising: a first
controller generating a first group key, executing first mutual
authentication with the one or more devices within the group, and
sharing the first group key with the one or more devices that have
succeeded in first mutual authentication, wherein the first
controller is included in the one or more controllers that belong
to the group; in a case where a second controller newly joins the
group, at least one controller deciding a coordinator that manages
a group key used in common in the group, from two or more
controllers including the one or more controllers and the second
controller newly joined in the group, in accordance with attributes
of the two or more controllers, wherein the at least one controller
is included in the two or more controllers; the first controller
executing second mutual authentication with the coordinator, and
sharing the first group key with the coordinator in a case where
the second mutual authentication is successful, the coordinator
performing encrypted communication within the group using the first
group key, the coordinator generating a second group key when valid
time of the first group key is equal to or smaller than a
predetermined value, executing third mutual authentication with the
one or more devices and a third controller, which is one or more
controllers included in the two or more controllers and which is
different from the coordinator, within the group, and updating the
first group key of the one or more devices and the third controller
that have succeeded in the third authentication to the second group
key.
2. The authentication method according to claim 1, further
comprising: the first controller transmitting authentication
information of the one or more devices within the network to the
coordinator, wherein the coordinator executes the third mutual
authentication using authentication information received from the
first controller.
3. The authentication method according to claim 1, wherein the one
or more devices within the group have a registration mode for
executing the third mutual authentication and registering another
party with which the third authentication has been successful,
wherein the two or more controllers within the group have a
registration mode for executing the second mutual authentication or
the third mutual authentication and registering another party with
which the second authentication or the third mutual authentication
has been successful, wherein in a case where the second mutual
authentication has been successful, the first controller further
transmits an activation instruction for the registration mode to
the coordinator and the one or more devices within the group,
wherein the one or more devices within the group receive the
activation instruction for the registration mode from the first
controller and activate the registration mode, and wherein the
coordinator receives the activation instruction for the
registration mode from the first controller and activates the
registration mode, and executes the third mutual authentication
with the one or more devices that have activated the registration
mode.
4. The authentication method according to claim 1, wherein each of
the two or more controllers stores a public key certificate in
which is described an attribute of itself, and wherein the at least
one controller decides the coordinator using the attributes
described in the public key certificates of the two or more
controllers.
5. The authentication method according to claim 4, wherein the
attribute described in the public key certificate is one of
dedicated, general-purpose, and application, wherein the attribute
of dedicated indicates that a corresponding controller only
provides dedicated functions for a particular object, wherein the
attribute of general-purpose indicates that the corresponding
controller provides functions for each a plurality of objects,
wherein the attribute of application indicates that the
corresponding controller is software that runs on a device
providing functions for each a plurality of objects, wherein a
controller of which the attribute is dedicated becomes a
coordinator with priority over controllers of which the attributes
are general-purpose and application, and wherein a controller of
which the attribute is general-purpose becomes a coordinator with
priority over controllers of which the attributes are
application.
6. The authentication method according to claim 4, wherein the
attributes described in the public key certificate are version
information, and wherein at least one controller decides the
coordinator in accordance with a version No. indicated by version
information described in each of the public key certificates in
which the two or more controllers store.
7. The authentication method according to claim 4, wherein the
attribute described in each of the public key certificates are
version information, and wherein the at least one controller
decides the coordinator in accordance with a corresponding device
count indicated by version information described in each of the
public key certificates of the two or more controllers.
8. The authentication method according to claim 1, wherein each of
the attributes of the two or more controllers is accumulated
running time of a corresponding controller.
9. The authentication method according to claim 1, wherein each of
the attributes of the two or more controllers is an elapsed time
from time of manufacturing of a corresponding controller.
10. The authentication method according to claim 1, wherein each of
the attributes of the two or more controllers is the number of
devices paired with a corresponding controller.
11. The authentication method according to claim 1, wherein the at
least one controller within the group has a display and operating
unit, and wherein the deciding by the at least one controller
further includes displaying, using the display, information
indicating the attributes of the two or more controllers; and
accepting, from the operating unit, user input selecting, as the
coordinator, one controller from the two or more controllers in the
group with regard to the display, wherein the selected one
controller is decided as the coordinator.
12. A first controller, comprising: a processor; and a memory that
stores a program that, when executed by the processor, causes the
processor to function as a connecting unit that connects to a group
to which one or more devices and one or more controllers on a
network belong, where one controller of the one or more controllers
generates a first group key, executes first mutual authentication
with the one or more devices within the group, and shares the first
group key with the one or more devices that have succeeded in the
first authentication; a negotiator that decides a coordinator that
manages a group key used in common in the group, from two or more
controllers, including the one or more controllers and the first
controller, in accordance with attributes of the two or more
controllers; an authentication processing unit that executes second
mutual authentication with the one of the one or more controllers
that receives the first group key from the one or more of the one
or more controllers that in a case where the second mutual
authentication is successful, and performs encrypted communication
within the group using the first group key, wherein, in a case
where the first controller itself is decided to be the coordinator,
the authentication processing unit further generates a second group
key when valid time of the first group key is equal to or smaller
than a predetermined value, receives authentication information of
the one or more devices within the group from the one of the one or
more controllers, executes third mutual authentication with the one
or more devices and the one or more controllers within the group
using the received authentication information, and updates the
first group key of the one or more devices and the one or more
controllers that have succeeded in the third authentication to the
second group key.
13. A first controller in one or more controllers, on a network,
which belongs to a group to which one or more devices further
belong, the controller comprising: a processor; and a memory that
stores a program that, when executed by a processor, causes the
processor to function as an authentication processing unit that
generates a first group key, that executes first mutual
authentication with the one or more devices within the group, and
that shares the first group key with the one or more devices that
have succeeded in the first mutual authentication; and a negotiator
that in a case where a second controller newly joins the group,
decides a coordinator that manages a group key used in common in
the group, from two or more controllers including the one or more
controllers and the second controller newly joined in the group, in
accordance with attributes of the two or more controllers, wherein
the authentication processing unit further executes second mutual
authentication with the coordinator, and shares the first group key
with the coordinator in a case where the second mutual
authentication is successful; transmits authentication information
of the one or more devices in the group to the coordinator; and
performs third mutual authentication with the coordinator, and in a
case where the third authentication is successful, receives a
second group key generated by the coordinator when valid time of
the first group key is equal to or smaller than a predetermined
value, and updates the first group key of the first controller to
the second group key.
Description
BACKGROUND
1. Technical Field
The present invention relates to technology of performing mutual
authentication between a controller and device connected to a
network, and sharing a group key.
2. Description of the Related Art
As of recent, there is expectation for services using various types
of history information collected from devices and the like
(hereinafter referred to simply as "devices") such as home
appliances, audio and visual (AV) devices, household equipment, and
so forth, that have network connection capabilities, and collected
in a server in a cloud.
A conceivable arrangement in such a service is to establish a
device that controls devices in the home (hereafter referred to as
"controller"), and the controller to relay communication between
the devices and the server in the cloud. In doing so, it is
required that the connection between the controller and the device
prevent information from leaking, such as spoofing by unauthorized
devices and interception of communication contents.
An example of countering spoofing by unauthorized devices that is
performed includes authentication of the legitimacy of controllers
and devices using public key infrastructure (PKI). An example of
countering information leakage is encrypted communication being
performed between controllers and devices of which the legitimacy
has been authenticated sharing a key for encrypted
communication.
In a case where there are multiple devices connecting to a
controller, the controller and the devices sharing the same key for
encrypted communication (hereinafter referred to as "group key")
enables encryption of multicast communication and broadcast
communication where the controller transmits the same information
to the devices at once.
For description of this technology, see Japanese Patent No.
4576997, Federal Information Processing Standards Publication (FIPS
PUB) 186-4: Digital Signature Standard (DSS), National Institute of
Standards and Technology (NIST), July 2013, and NIST Special
Publication 800-56A Revision 2: Recommendation for Pair-Wise Key
Establishment Schemes Using Discrete Logarithm Cryptography,
National Institute of Standards and Technology (NIST), May
2013.
SUMMARY
In one general aspect, the techniques disclosed here feature an
authentication method for a group to which one or more devices and
one or more controllers including a first controller on a network
belong. The method includes: the first controller generates a first
group key, executes first mutual authentication with devices within
the group, and shares the first group key with devices that have
succeeded in authentication; in a case where a second controller
newly joins the group, at least one controller within the group
decides a coordinator that manages a group key used in common in
the group, from controllers including the one or more controllers
and the second controller newly joined in the group, in accordance
with attributes of the controllers; the first controller executes
second mutual authentication with the coordinator, and shares the
first group key with the coordinator in a case where the
authentication is successful; the coordinator performs encrypted
communication within the group using the first group key; and the
coordinator generates a second group key when valid time of the
first group key is equal to or smaller than a predetermined value,
executes third mutual authentication with the devices and
controllers within the group, and updates the group key of the
devices and controllers that have succeeded in authentication to
the second group key.
According to the present disclosure, in a case where multiple
controllers exist in a group on a network, a suitable controller
can be selected as a coordinator that manages a group key used in
common within the group.
It should be noted that general or specific embodiments may be
implemented as a system, a method, an integrated circuit, a
computer program, a storage medium, or any selective combination
thereof.
Additional benefits and advantages of the disclosed embodiments
will become apparent from the specification and drawings. The
benefits and/or advantages may be individually obtained by the
various embodiments and features of the specification and drawings,
which need not all be provided in order to obtain one or more of
such benefits and/or advantages.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram illustrating an example of an authentication
system;
FIG. 2 is a diagram illustrating an example of a group
configuration within a home area network (HAN);
FIG. 3 is a diagram illustrating an example of a group
configuration after integration;
FIG. 4 is a diagram illustrating an example of a functional
configuration of a controller;
FIG. 5A is a diagram illustrating an example of a connected device
management table, that the controller stores;
FIG. 5B is a diagram illustrating an example of information
relating to a group, stored in the controller;
FIG. 6 is a diagram illustrating an example of a public key
certificate;
FIG. 7 is a diagram illustrating an example of a certificate
revocation list (CRL);
FIG. 8 is a diagram illustrating an example of a functional
configuration of a device;
FIG. 9A is a diagram illustrating an example of a connected
controller management table, that a device stores;
FIG. 9B is a diagram illustrating an example of information
relating to a group, stored in the device;
FIG. 10 is a sequence diagram illustrating an example of operations
of an authentication system at the time of registering a
device;
FIG. 11 is a sequence diagram illustrating an example of operations
of an authentication system when a controller joins;
FIG. 12 is a sequence diagram illustrating an example of
negotiation processing;
FIG. 13 is a sequence diagram illustrating an example of SC
(Security Coordinator) handover processing;
FIG. 14 is a sequence diagram illustrating an example of mutual
authentication processing;
FIG. 15 is a sequence diagram illustrating an example of processing
for calculating a shared key;
FIG. 16 is a sequence diagram illustrating an example of processing
for group key distribution/reception;
FIG. 17 is a sequence diagram illustrating an example of group key
updating processing;
FIG. 18 is a sequence diagram illustrating an example of group key
updating processing;
FIG. 19A is a diagram illustrating a connected device management
table, stored in a controller A before group integration;
FIG. 19B is a diagram illustrating information relating to a group,
stored in the controller A before group integration;
FIG. 19C is a diagram illustrating a connected device management
table, stored in a controller B before group integration;
FIG. 19D is a diagram illustrating information relating to the
group, stored in the controller B before group integration;
FIG. 20A is a diagram illustrating a connected controller
management table, stored the device A before group integration;
FIG. 20B is a diagram illustrating information relating to the
group, stored in the device A before group integration;
FIG. 20C is a diagram illustrating a connected controller
management table, stored in the device B before group
integration;
FIG. 20D is a diagram illustrating information relating to the
group, stored in the device B before group integration;
FIG. 21A is a diagram illustrating a connected device management
table, stored in the controller A after group integration;
FIG. 21B is a diagram illustrating information relating to the
group, stored in the controller A after group integration;
FIG. 21C is a diagram illustrating a connected device management
table, stored in the controller B after group integration;
FIG. 21D is a diagram illustrating information relating to the
group, stored in the controller B after group integration;
FIG. 22A is a diagram illustrating a connected controller
management table, stored the device A after group integration;
FIG. 22B is a diagram illustrating information relating to the
group, stored in the device A after group integration;
FIG. 22C is a diagram illustrating a connected controller
management table, stored in the device B after group
integration;
FIG. 22D is a diagram illustrating information relating to the
group, stored in the device B after group integration;
FIG. 23 is a sequence diagram illustrating an example of device
history information transmission processing;
FIG. 24 is a sequence diagram illustrating an example of control
command transmission processing;
FIG. 25 is a sequence diagram illustrating an example of SC
handover processing; and
FIG. 26 is a diagram illustrating an SC selection screen.
DETAILED DESCRIPTION
Background Leading to Present Disclosure
An arrangement is conceivable in a network such as a home area
network (HAN) or the like where multiple controllers control the
same device. In such an arrangement, each controller individually
generates a group key, distributes to the device, and the device
performs encrypted communication using a different group key for
each controller. However, there are some devices that cannot assign
appropriate resources necessary to perform encrypted communication
using multiple group keys. For example, there is the possibility
that the computation capabilities of a device may be low, and
encrypted communication cannot be performed using multiple group
keys. Also, in a case where the storage capacity of the device is
small, there is the possibility that not all group keys necessary
for encrypted communication with all controllers can be stored.
Accordingly, a configuration is conceivable where part or all of
the devices and controllers on a network configure a group, a
controller to manage the group key is selected from the controllers
in the group, the controller that is decided upon generates a group
key, and distributes this to the devices and controllers within the
group. However, this configuration has a problem with regard to
which controller is to manage the group key. For example, some
controllers may frequently experience power cutoff or state of
disconnect from the network, and not be able to communicate with
other devices and controllers at all times. Randomly deciding the
controller to manage the group key can result in such a controller
being selected. In a state where communication cannot be performed
with controller managing the group key, new devices or controllers
cannot join the group and share the group key. It also is desirable
to periodically update the group key from a security perspective,
but in a state where communication cannot be made with the
controller managing the group key, the group key cannot be updated.
The conventional authentication system has needed further
improvement regarding group keys. The present disclosure provides
an authentication method for deciding a suitable controller as a
controller to manage a group key used in common within a group, in
a case where multiple controllers exist within a group on a
network.
First Embodiment
The authentication system according to embodiments of the present
disclosure will be described below with reference to the drawings.
Note that values, shapes, materials, components, placements and
connected states of components, steps, and the order of steps, and
so forth illustrated in the following embodiments, are only
exemplary, and do not restrict the present disclosure.
Overview
The overview of an authentication system 100 will be described here
as an embodiment of the present disclosure. FIG. 1 is a diagram
illustrating the configuration of the authentication system 100.
The authentication system 100 is configured including a controller
110 (controller 110a and controller 110b) and device 120 (devices
120a, 120b, and 120c) on a HAN 130. The controller 110 is also
connected to a server 140 (server 140a and server 140b) via a
network 150.
The device 120 is a home appliance, AV device, or household
equipment, having functions to connect to a network, examples
including a television, recorder, air conditioner refrigerator,
battery, and so forth. The controller 110 is a device having
functions of controlling a device 120, and generates control
commands in accordance with being commissioned by the server 140
for example, and the generated commands are transmitted to the
device 120 to be executed. The controller 110 also has a function
of transmitting information stored in the device 120 to the server
140. The controller 110 controls devices 120 that are registered by
pairing, and the devices 120 execute control commands transmitted
from a controller 110 registered by pairing.
The HAN 130 is a wired or wireless network constructed within the
home. The HAN 130 is specifically realized by Ethernet (a
registered trademark), specified low power radio (a Japanese
standard), Wi-Fi (a registered trademark), Bluetooth (a registered
trademark), power-line communication, or the like. The network 150
is a network configured between the home and a corporation or the
like, which may or may not be interconnected by the Internet.
In the authentication system 100, one group is formed that shares
one group key among one or more controllers 110 on the HAN 130, and
one or more devices 120 that have paired with the one or more
controllers 110. The group key is generated by a controller 110,
and is distributed from controller 110 to device 120 when the
controller 110 and device 120 perform authentication processing or
the like.
FIG. 2 is a diagram illustrating an example of group configurations
of controllers 110 and devices 120 on the HAN 130. FIG. 2
illustrates a group 200 to which a controller A and device A
belong, and a group 210 to which a controller B and device B
belong. The group 200 and group 210 share different group keys.
Accordingly, even if group 200 and group 210 use the same
communication method, the contents being communicated within each
other's group will not leak outside of the group.
When pairing occurs between devices or controllers belonging to
different groups in the authentication system 100, the two groups
are integrated. For example, in a case where the device A and
controller B are paired in the state of group configurations
illustrated in FIG. 2, the group configuration is changed to that
illustrated in FIG. 3. At this time, the authentication system 100
decides on one of the controllers to perform authentication
processing and group key management processing, and the controller
that is decided upon undertakes generating and distribution of the
group key. In the present disclosure, the controller that performs
authentication processing and group key management processing is
called an SC (Security Coordinator). Note that devices and
controllers other than the SC may be referred to as nodes. In the
example in FIG. 3, the controller A has been decided to be the SC.
That is to say, only the controller A, that is the SC, performs
authentication processing with the devices and group key generation
and distribution in the group 300, and the controller B does not.
The controller B uses the group key that the controller A, that is
the SC, has generated and distributed, to control the device A and
device B regarding which pairing has been performed.
Configuration
Next, the configuration of the controller 110 and device 120, which
are primary components of the authentication system 100, will be
described.
Configuration of Controller
First, the configuration of the controller 110 will be described
with reference to FIGS. 4 through 7. FIG. 4 is a diagram
illustrating the functional configuration of the controller 110.
The controller 110 includes a device managing unit 410, a device
information storing unit 420, an authentication processing unit
430, an authentication information storing unit 440, a negotiating
unit 450, an operating unit 460, and a communication unit 470.
The device managing unit 410 manages devices 120 and other
controllers 110 connected to its device (the controller 110). The
device managing unit 410 functions to accept pairing requests and
mutual authentication requests from devices 120 and other
controllers 110 via the communication unit 470, group key update
requests from the device information storing unit 420, and so
forth, commission the authentication processing unit 430 and so
forth to perform processing according to the request, and updates a
connected device management table 500 and group-related information
510, stored in the device information storing unit 420, in
accordance with the results of the commissioning.
FIG. 5A is a diagram illustrating an example of the connected
device management table 500 stored in the device information
storing unit 420. FIG. 5B is a diagram illustrating an example of
the group-related information 510 stored in the device information
storing unit 420.
The connected device management table 500 has recorded therein, for
every device 120 (or other controller 110) connected to itself (the
controller 110), a device ID 501, certificate ID 502, shared key
503, group key 504, group key valid time 505, and group key update
flag 506. The device ID 501 is information for uniquely identifying
the device 120. The certificate ID 502 is a certificate ID of a
public key certificate that the device 120 has. The shared key 503
is data of a shared key shared with the device 120. The group key
504 is data of a group key set to the device 120. The group key
valid time 505 is the remaining time in the valid period of the
group key set to the device 120. The group key update flag 506 is
flag information indicating whether or not the group key of the
device 120 has been updated to the newest.
Group-related information 510 has recorded therein controlling
device 511, SC 512, and affiliated devices 513. The controlling
device 511 is the device ID of the device 120 regarding which
pairing has been performed with. The SC 512 is the device ID of the
SC of the group to which the SC belongs. Note that the SC 512 of
the controller 110 is set to a value indicating its own device ID
of when shipping. The affiliated devices 513 are device IDs of
devices 120 and other controllers 110 belonging to the group under
the SC itself.
The device information storing unit 420 functions to cause the
value of the group key valid time 505 to be counted down along with
elapsing of time, and in a case where the value of the group key
valid time 505 is a predetermined value or lower, performs a group
key update request to the device managing unit 410. The
predetermined value is such as, for example, a value that is 10% of
the initially set value, a value twice the time necessary to update
the group key, or the like.
Returning to FIG. 4, description of the configuration of the
controller 110 will be continued. The authentication processing
unit 430 functions to perform authentication processing with
devices 120 and other controllers 110 in accordance with a
commission from the device managing unit 410. Details of the
authentication processing performed by the authentication
processing unit 430 will be described later.
The authentication information storing unit 440 stores the secret
key and public key certificate of its device (the controller 110).
The authentication information storing unit 440 also stores a
certificate revocation list (CRL) used to confirm that the public
key certificate of the device of another party has not been
revoked, and a digital certificate including the public key of a
certifying authority. Note that the key pair of the secret key and
public key certificate, CRL, and digital certificate, have been
embedded when the controller 110 ships.
FIG. 6 is a diagram illustrating an example of the data
configuration of a public key certificate 600 that the
authentication information storing unit 440 stores. The public key
certificate 600 is configured including data of version 610,
certificate ID 620, signature 630, issuing party 640, start of
valid period 650, end of valid period 660, public key 670, and
attribute 680, for example.
FIG. 7 is a diagram illustrating an example of the data
configuration of a CRL 700 that the authentication information
storing unit 440 stores. The CRL 700 is configured including data
of version 710, signature 720, issuing party 730, date issued 740,
next date of issue 750, and revoked certificate IDs, for
example.
Returning to FIG. 4, description of the configuration of the
controller 110 will be continued. In a case where there are
multiple controllers 110 within a single group, and pairing has
occurred between devices belonging to different groups or the like,
for example, the negotiating unit 450 communicates with other
controllers 110, and performs negotiation processing to decide
which controller will be the SC. Details of the negotiation
processing performed by the negotiating unit 450 will be described
later.
The functional units that are the device managing unit 410, device
information storing unit 420, authentication processing unit 430,
authentication information storing unit 440, and negotiating unit
450, typically are realized by a processor executing a program
stored in memory.
The operating unit 460 is configured including a pairing button,
and a control circuit that generates an interrupt signal in
accordance with the pressing of this button and notifies the
processor.
The communication unit 470 is realized by a communication Large
Scale Integration (LSI) having communication functions. The
communication unit 470 is connected to the HAN 130 and to the
network 150, and has functions of communicating with devices 120
and other controllers 110 connected to the HAN 130 via the HAN 130,
and communicating with the server 140 via the network 150.
Connection between the controller 110 and the network 150 may be
performed via a gateway device omitted from illustration.
The communication unit 470 performs encrypted communication as
suitable using the group key received from the authentication
processing unit 430 or the like to communicate with devices 120 and
other controllers 110. The communication unit 470 preforms Secure
Socket Layer (SSL) communication for communication with the server
140. The communication unit 470 stores certificates and the like
necessary for SSL communication.
Configuration of Device
Next, the configuration of the device 120 will be described with
reference to FIGS. 8 through 9B. FIG. 8 is a diagram illustrating
the functional configuration of the device 120. The device 120 is
configured including a device managing unit 810, a device
information storing unit 820, an authentication processing unit
830, an authentication information storing unit 840, a device
history storing unit 850, an operating unit 860, and a
communication unit 870.
The device managing unit 810 manages controllers 110 connected to
itself (the device 120). The device managing unit 810 functions to
activate a registration mode with an interruption signal from the
operating unit 860 as a trigger and transmit a pairing request to a
controller 110, and also functions to update a connected controller
management table 900 and group-related information 910, stored in
the device information storing unit 820, in accordance to
processing results by the authentication processing unit 830 and so
forth. The device managing unit 810 also functions to encrypt
device history information recorded in the device history storing
unit 850 using the group key, and periodically or non-periodically
transmit to the server 140 via the controller 110.
FIG. 9A is a diagram illustrating an example of the connected
controller management table 900 that the device information storing
unit 820 stores. FIG. 9B is a diagram illustrating an example of
group-related information 910, that the device information storing
unit 820 stores.
The connected controller management table 900 records a controller
ID 901, certificate ID 902, shared key 903, and group key 904, for
each controller 110 to which its device (the device 120) connects.
The controller ID 901 is information for uniquely identifying the
controller 110. The certificate ID 902 is a certificate ID of a
public key certificate that the controller 110 has. The shared key
903 is data of a shared key shared with the controller 110. The
group key 904 is data of a group key received from the controller
110. Note that the shared key is shared only with the SC, and not
shared with all controllers.
The group-related information 910 records a controlling controller
911 and SC 912. The controlling controller 911 is the device ID of
a controller 110 with which pairing has been performed. The SC 912
is the device ID of the SC of the group. At the time of shipping of
the device, the SC 912 of the device 120 is set to a value
indicating that no SC has been registered.
Returning to FIG. 8, description of the configuration of the device
120 will be continued. The authentication processing unit 830
functions to perform authentication processing with controllers 110
Details of the authentication processing performed by the
authentication processing unit 830 will be described later.
The authentication information storing unit 840 stores the secret
key and public key certificate of its device (the device 120). The
authentication information storing unit 840 also stores a CRL and a
digital certificate including the public key of a certifying
authority. The public key certificate and CRL are the same as the
public key certificate and CRL that the controller 110 stores, and
accordingly description will be omitted here. Note that the key
pair of the secret key and public key certificate, the CRL, and
digital certificate have been embedded when the device 120 ships.
The device history storing unit 850 stores device history
information indicating operating history of its device (the device
120).
The functional units that are the device managing unit 810, device
information storing unit 820, authentication processing unit 830,
authentication information storing unit 840, and device history
storing unit 850, typically are realized by a processor executing a
program stored in memory.
The operating unit 860 is configured including a pairing button,
and a control circuit that generates an interrupt signal in
accordance with the pressing of this button and notifies the
processor.
The communication unit 870 is realized by a communication LSI
having communication functions. The communication unit 870 is
connected to the HAN 130, and has functions of communicating with
controllers 110 connected to the HAN 130 via the HAN 130.
The communication unit 870 performs encrypted communication as
suitable using the group key received from the authentication
processing unit 830 or the like to communicate with controllers
110.
Operations
Device registration processing, negotiation processing, SC handover
processing, mutual authentication processing, shared key
calculation processing, group key distribution/reception
processing, group key updating processing, device history
information transmission processing, and control command
transmission processing, performed in the authentication system
100, will be described below in order.
Device Registration Processing
Device registration processing is processing when a controller and
device pair. The device registration processing will be described
below with reference to FIG. 10. Note that a device A and
controller B are performing device registration processing in the
following description.
(S1000) The user presses the pairing buttons that the device A and
controller B have. Accordingly, the registration mode is activated
in each of the device A and controller B.
(S1005) The device A transmits a connection request to the
controller B. At this time, the device A transmits the device ID of
the SC set in itself as well. In a case where no SC has been set to
the device A, information to that effect is transmitted.
(S1010) The controller B determines whether or not negotiation
processing is necessary, based on the device ID of the SC set to
itself, and the device ID of the SC notified from the device A. In
the authentication system 100, in a case where different
controllers are set as the SC between the device A and controller
B, negotiation processing is necessary. On the other hand, in a
case where no SC has been set to the device A, or in a case where a
common controller is set as the SC for the device A and controller
B, there is no need to perform negotiation processing.
(S1015) In a case where determination has been made in step S1010
that negotiation processing is necessary, negotiation processing is
performed between the controller set as the SC for the device A and
the controller set as the SC for the controller B.
In a case where the controller B itself is going to perform the
negotiation processing, the controller B transmits a negotiation
request to the other party with which the negotiation processing is
to be performed, and starts the negotiation processing. In a case
where the controller B itself is not going to perform the
negotiation processing, the controller B transmits a negotiation
request to the two controllers that will perform the negotiation
processing. Details of negotiation processing will be described
later.
(S1020) The controller B transmits the device ID of the SC to the
device A. In a case where determination has been made in step S1010
that negotiation processing is not necessary, the controller B
notifies of the device ID of the SC set to itself. In a case where
determination has been made in step S1010 that negotiation
processing is necessary, the controller B acquires the device ID of
the controller newly decided to be the SC as a result of the
negotiation processing, and transmits to the device A.
(S1025) The device A and controller B determine whether or not
authentication is necessary between themselves and the SC. In a
case where the device ID notified from the controller B in step
S1020 and the device ID of the controller currently set to the
device A as the SC differ, or in a case where the device A does not
share the group key generated by the SC notified from the
controller B or the like, the device A determines that
authentication is necessary. In a case where the device ID
transmitted the device A in step S1020 and the device ID of the
controller currently set to the controller B as the SC differ, or
in a case where the controller B does not share the group key
generated by the SC transmitted to the device A or the like, the
controller B determines that authentication is necessary.
(S1030, S1035) In a case where determination is made in step S1025
that authentication is necessary, the device A or controller B
perform later-described mutual authentication processing and group
key distribution/reception processing with the new SC.
(S1040) In a case where the mutual authentication processing and
group key distribution/reception processing have ended
successfully, the device A or controller B perform processing to
join affiliation under the new SC. The device A sets the device ID
of the new SC in the SC 912 of the group-related information 910
that the device information storing unit 820 stores. Alternatively,
the controller B sets the device ID of the new SC in the SC 512 of
the group-related information 510 stored in the device information
storing unit 420. The device A or controller B transmit their own
device IDs to the new SC, and the SC sets the received device ID in
the group-related information 510 saved in the device information
storing unit 420, as an affiliated device 513.
(S1045) In a case where the mutual authentication processing and
group key distribution/reception processing of the device A or
controller B has ended successfully, the device A transmits a
pairing request to the controller B. The device A also transmits
its own device ID at this time.
(S1050) Upon receiving the pairing request from the device A, the
controller B performs pairing with the device A. That is to say,
the controller B sets the device ID received from the device A
along with the pairing request as a controlling device 511 in the
group-related information 510 stored in the device information
storing unit 420.
(S1055) Upon having perform pairing with the device A, the
controller B transmits a pairing request to the device A. The
controller B also transmits its own device ID at this time.
(S1060) Upon receiving the pairing request from the controller B,
the device A performs pairing with the controller B. That is to
say, the device A sets the device ID received from the controller B
along with the pairing request as a controlling controller 911 in
the group-related information 910 stored in the device information
storing unit 820.
(S1065) Upon pairing with each other having ended successfully, the
device A and controller B end the registration mode, and notify
other devices and controllers belonging to the same group that
pairing has been performed between the device A and controller B.
This notification is encrypted using the group key shared in step
S1035, and transmitted by broadcasting or the like. The
above-described is device registration processing carried out
between the device A and controller B.
FIG. 11 illustrates processing in a case where device registration
processing is carried out between a controller A and controller B.
The device registration processing between the controller A and
controller B is the same as the device registration processing
between the device A and controller B, except that the processing
of steps S1045, S1050, S1055, and S1060 is not performed, so
description will be omitted.
Negotiation Processing
Negotiation processing is processing performed when pairing has
occurred between devices and controllers belonging to different
groups, to decide which controller will be the SC after the two
groups have been integrated. Description of negotiation processing
will be made below with reference to FIG. 12. The following is
regarding negotiation processing between a controller A and
controller B.
(S1200) The controller A transmits a negotiation request to the
controller B.
(S1205) The controller A and controller B perform later-described
mutual authentication processing.
(S1210) In a case where the mutual authentication processing has
ended successfully, the controller A acquires attributes of the
controllers from the public key certificate of the controller A and
the public key certificate of the controller B obtained in the
mutual authentication processing.
(S1215) The controller A determines whether or not the attribute of
the controller A is "dedicated device". In a case where the
attribute of the controller A is "dedicated device", the flow
advances to step S1235; otherwise, to step S1220.
(S1220) The controller A determines whether or not the attribute of
the controller B is "dedicated device". In a case where the
attribute of the controller B is "dedicated device", the flow
advances to step S1240; otherwise, to step S1225.
(S1225) The controller A determines whether or not the attribute of
the controller A is "general-purpose device". In a case where the
attribute of the controller A is "general-purpose device", the flow
advances to step S1235; otherwise, to step S1230.
(S1230) The controller A determines whether or not the attribute of
the controller B is "general-purpose device". In a case where the
attribute of the controller B is "general-purpose device", the flow
advances to step S1240; otherwise, to step S1235.
(S1235) The controller A decides the controller A to be the SC.
(S1240) The controller A decides the controller B to be the SC.
(S1245) The controller A notifies the selection results of the SC
to the controller B.
(S1250) The controller A and controller B perform later-described
SC handover processing.
This so far has been a description of negotiation processing. In
the negotiation processing, data in the attribute item of the
public key certificate is referenced, and the order of priority in
becoming an SC is changed depending on whether the controller is a
"dedicated device" that only has functions of controlling other
devices, a "general-purpose device" that has other functions as
well, or an "application" that runs on a PC, smartphone, or the
like. If the attribute of the controller is "dedicated device", it
is conceivable that the controller will have a function to always
be in standby, so that processing can be quickly performed at any
time. If the attribute of the controller is "general-purpose
device", it is conceivable that the power may go off when everyone
has left the house or gone to bed. If the attribute of the
controller is "application", it is conceivable that the power may
go off or the controller may disconnect from the network at any
time. Accordingly, the order of priority to be the SC is set in the
order of "dedicated device", "general-purpose device", and
"application". In a case where the attributes of the two are the
same, description is made here regarding a case where the
controller that has commissioned the negotiation processing becomes
the SC with priority, but the controller B that has received the
commission for negotiation processing may become the SC with
priority.
SC Handover Processing
SC handover processing is processing for the controller that had
been the SC so far, to hand information that it had stored to the
new SC, after the new SC has been decided by the negotiation
processing. This SC handover processing will be described below
with reference to FIG. 13. In the following description, the SC
handover processing is carried out between the controller A that
has newly become the SC (new SC) and the controller B that had been
the SC so far (old SC).
(S1300) The new SC and old SC perform later-described group key
distribution/reception processing. Here, the group key managed by
the old SC is distributed to the new SC.
(S1305) The old SC transmits information of the affiliated devices
under itself to the new SC. Specifically, data of the device ID
501, certificate ID 502, group key 504, and group key valid time
505, in the connected device management table 500, for each
affiliated device 513 in the group-related information 510 of the
old SC, is transmitted. The old SC transmits the public key
certificate of the affiliated devices at this time as well. When
transmitting the group key to the new SC, the old SC encrypts the
group key using the shared key shared with the new SC and
transmits.
(S1310) The old SC notifies the affiliated devices under itself
that the SC has changed from the controller B to the controller A.
The old SC also transmits the device ID and public key certificate
of the controller A at this time.
(S1315) Upon receiving the notification of changing the SC and the
device ID and public key certificate from the old SC, the
affiliated devices under the old SC register the controller A as
the SC. Specifically, the affiliated devices under the old SC
register the device ID of the controller A that has been received
in the SC 912 in the group-related information 910 stored in the
device information storing unit 820. Further, the affiliated
devices under the old SC add the record of the device ID of the
controller A that has been received in the connected controller
management table 900.
(S1320) The new SC uses the group key received in the group key
distribution/reception processing in step S1300 and the device
information received in step S1305 to update the connected device
management table 500 and the group-related information 510 stored
in the device information storing unit 420.
(S1325) The old SC registers the controller A, which is the new SC,
as the SC. Specifically, the old SC sets the device ID of the
controller A in the SC 512 of the group-related information 510
stored in the device information storing unit 420.
(S1330) The affiliated devices under the old SC and the new SC
perform later-described shared key calculation processing. The
timing for the shared key calculation processing may be immediately
after the affiliated devices under the old SC register the new SC
as the SC, or may be any time before the new SC updates the group
key. This so far has been a description of SC handover
processing.
Mutual Authentication Processing
Next, mutual authentication processing between a device or
controller and a controller will be described with reference to
FIG. 14. Although description will be made below regarding mutual
authentication processing between a device and a controller, the
same processing is performed regarding mutual authentication
processing between a controller and a controller.
(S1400) An authentication request is transmitted from the device to
the controller. The device also transmits its own device ID and
public key certificate at this time.
(S1405) The controller verifies that the certificate ID of the
public key certificate of the device is not listed in the CRL
stored in the authentication information storing unit 440. In a
case where verification fails, the controller notifies the device
of the error, and the processing ends.
(S1410) Upon confirming that the certificate ID is not listed in
the CRL, the controller verifies the signature of the public key
certificate of the device using a public key of a certificate
authority. In a case where the verification fails, the controller
notifies the device of the error and the processing ends. A
commonly-used method such as Elliptic Curve Digital Signature
Algorithm (ECDSA), RSA, DSA (Digital Signature Algorithm), or the
like, may be used for the signature. Upon succeeding in verifying
the signature of the public key certificate of the device, the
controller creates a new record in the connected device management
table 500, and registers the device ID and certificate ID of the
device which is to be the other party in the mutual authentication
processing.
(S1415) Upon succeeding in verifying the signature of the public
key certificate of the device, the controller transmits its own
device ID and public key certificate to the device.
(S1420) The device verifies that the certificate ID of the public
key certificate of the controller is not listed in the CRL stored
in the authentication information storing unit 840. In a case where
verification fails, the device notifies the controller of the
error, and the processing ends.
(S1425) Upon confirming that the certificate ID is not listed in
the CRL, the device verifies the signature of the public key
certificate of the controller using a public key of a certificate
authority. In a case where the verification fails, the device
notifies the controller of the error and the processing ends. Upon
succeeding in verifying the signature of the public key certificate
of the controller, the device creates a new record in the connected
controller management table 900, and registers the device ID and
certificate ID of the controller which is to be the other party in
the mutual authentication processing.
(S1430) The device and controller perform later-described shared
key calculation processing. This so far has been a description of
mutual authentication processing.
Shared Key Calculation Processing
Next, the shared key calculation processing between the device or
controller and controller will be described with reference to FIG.
15. Although description will be made below regarding shared key
calculation processing between a device and a controller, the same
processing is performed regarding shared key calculation processing
between a controller and a controller.
(S1500) The device and controller perform key exchange. A common
method such as Elliptic Curve Diffie-Hellman (ECDH) key exchange or
the like may be used for the key exchange. ECDH can use either
static keys or Ephemeral keys. While the present embodiment uses
static keys, this is not restrictive, and an arrangement may be
made where ephemeral keys are used.
(S1505) The device and controller calculate the shared key.
Specifically, the device and controller calculate a hash value
regarding a value shared in the key exchange in step S1500, and use
the highest 128 bits of the calculated hash value as a shared key.
Although the authentication system 100 uses 128-bit length AES
(Advanced Encryption Standard) as the encryption method using the
shared key, this is not restrictive, and other encryption methods
may be used. The device registers the calculated shared key in the
shared key 903 of the record for the corresponding controller in
the connected controller management table 900. The controller
registers the calculated shared key in the shared key 503 of the
record for the corresponding device in the connected device
management table 500. The corresponding controller and
corresponding device are the device and controller that are the
other parties in the shared key calculation processing.
(S1510, S1515) The controller generates a random number A, and
transmits this to the device.
(S1520) The device encrypts the random number A received from the
controller using the shared key calculated in step S1505, thereby
generating an encrypted random number A'.
(S1525, S1530) The device generates a random number B, and
transmits the encrypted random number A' and random number B to the
controller.
(S1535) The controller decrypts the encrypted random number A'
received from the device using the shared key calculated in step
S1505, and performs verification whether this matches the random
number A generated in step S1510. In a case where verification
fails, the controller notifies the device of the error, and the
processing ends.
(S1540, S1545) The controller encrypts the random number B received
from the device using the shared key calculated in step S1505,
thereby generating an encrypted random number B', which is
transmitted to the device.
(S1550) The device decrypts the encrypted random number B' received
from the controller using the shared key calculated in step S1505,
and performs verification whether this matches the random number B
generated in step S1525. In a case where verification fails, the
device notifies the controller of the error, and the processing
ends.
(S1555) In a case where verification is successful, the device
notifies the controller of the results of success in verification.
This so far has been a description of shared key calculation
processing.
Group Key Distribution/Reception Processing
Next, group key distribution/reception processing between a device
or a controller that is not the SC, and a controller that is the
SC, will be described with reference to FIG. 16. Although the
description below is made regarding group key
distribution/reception processing between a device and a controller
that is the SC, this may be carried out between a controller that
is not the SC and a controller that is the SC. In this case, the
device is substituted with a controller that is not the SC.
(S1600) The controller determines whether or not a group key has
already been generated. In a case where a group key has already
been generated, the group key that has already been generated and
the group key valid time are registered in the record for the
corresponding device in the connected device management table 500
by the controller. The corresponding device here is the device
serving as the other part in the group key distribution/reception
processing.
(S1605, S1610) In a case where a group key has not already been
generated, the controller generates a group key, and decides a
valid time for the generated group key. Although the authentication
system 100 uses 128-bit length AES as the encryption method using
the group key, this is not restrictive, and other encryption
methods may be used. The controller registers the generated group
key and the group key valid time in the record for the
corresponding device in the connected device management table
500.
(S1615, S1620) The controller encrypts the generated or
already-generated group key using the shared key in the record for
the corresponding device in the connected device management table
500, thereby generating an encrypted group key, which is
transmitted to the device.
(S1625) The device decrypts the encrypted group key received from
the controller using the shared key in the record of the
corresponding controller in the connected controller management
table 900.
(S1630) The device records the group key decrypted in step S1625 in
the record for the corresponding controller in the connected
controller management table 900.
(S1635) the device notifies the controller that group key
registration has been completed.
(S1640) The controller registers a value, indicating that the group
key has already been updated, to a group key updating flag 506 in
the record for the corresponding device in the connected device
management table 500. This so far has been a description of group
key distribution/reception processing.
In a case of sharing a group key between controllers, the group key
valid time may also be encrypted and transmitted when encrypting
and transmitting the group key in steps S1615 and S1620. A
controller receiving the encrypted group key valid time may
register the received group key valid time in the connected device
management table 500.
Group Key Updating Processing
Next, group key updating processing between the SC controller, and
affiliated devices and controllers under the SC, will be described
with reference to FIG. 17.
(S1700) The controller that has become the SC determines whether or
not the group key valid time 505 of any one of the records in the
connected device management table 500 is a predetermined value or
lower. The following processing is not carried out until the group
key valid time is the predetermined value or lower.
(S1705) When the group key valid time 505 of any one of the records
in the connected device management table 500 is a predetermined
value or lower, the SC generates a new group key.
(S1710) The SC decides the valid time for the group key generated
in step S1705. The valid time is decided to be a value such as 24
hours or 72 hours, for example.
(S1715) The SC registers a value indicating that the group key has
not been updated, to the group key update flag 506 for all records
in the connected device management table 500.
(S1720) The SC decides one device (or controller) for updating the
group key, from the affiliated devices and controllers under
itself.
(S1725) The SC generates an encrypted group key by encrypting the
group key generated in step S1705, using the shared key in the
record for the device (or controller) decided in step S1720 in the
connected device management table 500.
(S1730) The SC transmits the encrypted group key generated in step
S1725 to the device decided in step S1720, and updates the group
key in the device (or controller) decided in step S1720. The
processing of step S1730 will be described later in detail.
(S1735) The SC determines whether group key updating has been
performed for all affiliated devices and controllers under itself.
In a case where there is a device or controller regarding which the
group key has not been updated, the flow returns to step S1720,
while in a case where the group key has been updated for all
affiliated devices and controllers underneath, the flow advances to
step S1740.
(S1740) The SC registers the group key generated in step S1705 in
the group key 504 in all records of the connected device management
table 500. The SC registers the group key valid time that has been
decided in the group key valid time 505 in all records in the
connected device management table 500.
Next, the detailed processing of step S1730 will be described with
reference to FIG. 18. Although the description below is made
regarding processing between the device decided in step S1720 and a
controller that is the SC, this may be carried out between a
controller decided in step S1720 and a controller that is the SC.
In this case, the device is substituted with a controller that is
not the SC.
(S1800, S1805) The SC generates a random number A, and transmits
the random number A to the device along with a group key update
request.
(S1810) Upon receiving the group key update request and the random
number A from the SC, the device uses the shared key in the record
of the SC in the connected controller management table 900 to
encrypt the random number A, thereby generating an encrypted random
number A'.
(S1815, S1820) The device generates a random number B, and
transmits the encrypted random number A' and random number B to the
SC.
(S1825) The SC decrypts the encrypted random number A' received
from the device using the shared key of the record for the
corresponding device in the connected device management table 500,
and verifies whether or not this matches the random number A
generated in step S1800. In a case where verification fails, the SC
notifies the device of the error, and the processing ends.
(S1830, S1835) The SC uses the shared key of the record for the
corresponding device in the connected device management table 500
to encrypt the random number B received from the device, thereby
generating an encrypted random number B', and transmits this to the
device.
(S1840) The device decrypts the encrypted random number B' received
from the SC using the shared key of the record for the SC in the
connected controller management table 900, and verifies whether or
not this matches the random number B generated in step S1815. In a
case where verification fails, the device notifies the SC of the
error, and the processing ends.
(S1845) In a case where verification is successful, the device
notifies the SC of the results of success in verification.
(S1850) Upon receiving the results of successful verification from
the device, the SC transmits the encrypted group key generated in
step S1725 to the device.
(S1855) The device decrypts the encrypted group key received from
the SC using the shared key of the record for the SC in the
connected controller management table 900.
(S1860) The device registers the decrypted group key in the group
key 904 in all records of the connected controller management table
900.
(S1865) The device transmits a group key update completion
notification to the SC.
(S1870) Upon receiving a group key update completion notification
from the device, the SC registers a value indicating that the group
key is already updated, in the group key update flag 506 of the
record for the corresponding device in the connected device
management table 500. This so far has been a description of group
key updating processing.
Device History Information Transmission Processing
Next, processing for transmitting device history information from a
paired device to a controller will be described with reference to
FIG. 23. Note that this device history information transmission
processing is performed periodically or non-periodically.
(S2300) The device encrypts the device history information stored
in the device history storing unit 850 using the group key in the
connected controller management table 900, thereby generating
encrypted history information.
(S2305) The device transmits the encrypted history information
generated in step S2300 to the controller registered as the
controlling controller 911 in the group-related information
910.
(S2310) Upon receiving the encrypted device history information
from the device with which it has been paired, the controller
decrypts the encrypted device history information using the group
key in the record for the corresponding device in the connected
device management table 500.
This so far has been a description of device history information
transmission processing. Note that the controller may transmit the
decrypted device history information to an external server or the
like.
Control Command Transmission Processing
Next, processing for transmitting a control command from a
controller to a device that have been paired will be described with
reference to FIG. 24. Note that this control command transmission
processing is performed periodically or non-periodically.
(S2400) The controller generates control commands for the paired
devices based on a control request from an external server or the
like.
(S2405) The controller encrypts the control commands that have been
generated, using the group key in the record for the corresponding
device in the connected device management table 500, thereby
generating encrypted control commands.
(S2410) The controller transmits the encrypted control commands
that have been generated to the paired devices. In a case of
transmitting the same control command encrypted by the same group
key to multiple devices, the controller transmits by broadcast
communication.
(S2415) Upon receiving the encrypted control commands from the
controller with which they have been paired, the devices decrypt
using the group key in the connected controller management table
900.
(S2420) The devices execute the decrypted control commands. This so
far has been a description of control command transmission
processing.
Regarding Updating Connected Device Management Table and
Group-Related Information
The authentication system 100 operates while performing group
integration of the group configuration such as from the state
illustrated in FIG. 2 to the state illustrated in FIG. 3, by
appropriately carrying out the above-described device registration
processing, negotiation processing, SC handover processing, mutual
authentication processing, shared key calculation processing, and
group key distribution/reception processing.
Now, assumption will be made that the controller A and controller B
perform device registration processing in a state where the group
configuration within the HAN is as illustrated in FIG. 2, and a
group configuration such as illustrated in FIG. 3 has been achieved
through group integration. Updating of the connected device
management table 500 and group-related information 510 of the
controllers, and the connected controller management table 900 and
group-related information 910 of the devices, will be described
with reference to FIGS. 19A through 22D.
FIG. 19A is a diagram illustrating the connected device management
table 500 stored in the controller A when the group configuration
within the HAN is in the state in FIG. 2. FIG. 19B is a diagram
illustrating the group-related information 510 stored in the
controller A when the group configuration within the HAN is in the
state in FIG. 2. FIG. 19C is a diagram illustrating the connected
device management table 500 stored in the controller B when the
group configuration within the HAN is in the state in FIG. 2. FIG.
19D is a diagram illustrating the group-related information 510
stored in the controller B when the group configuration within the
HAN is in the state in FIG. 2.
FIG. 20A is a diagram illustrating the connected controller
management table 900 stored in the device A when the group
configuration within the HAN is in the state in FIG. 2. FIG. 20B is
a diagram illustrating the group-related information 910 stored in
the device A when the group configuration within the HAN is in the
state in FIG. 2. FIG. 20C is a diagram illustrating the connected
controller management table 900 stored in the device B when the
group configuration within the HAN is in the state in FIG. 2. FIG.
20D is a diagram illustrating the group-related information 910
stored in the device B when the group configuration within the HAN
is in the state in FIG. 2.
FIG. 21A is a diagram illustrating the connected device management
table 500 stored in the controller A after SC handover processing.
FIG. 21B is a diagram illustrating the group-related information
510 stored in the controller A after SC handover processing. FIG.
21C is a diagram illustrating the connected device management table
500 stored in the controller B after SC handover processing. FIG.
21D is a diagram illustrating the group-related information 510
stored in the controller B after SC handover processing.
FIG. 22A is a diagram illustrating the connected controller
management table 900 stored in the device A after SC handover
processing. FIG. 22B is a diagram illustrating the group-related
information 910 stored in the device A after SC handover
processing. FIG. 22C is a diagram illustrating the connected
controller management table 900 stored in the device B after SC
handover processing. FIG. 22D is a diagram illustrating the
group-related information 910 stored in the device B after SC
handover processing.
Comparing FIG. 19A and FIG. 21A, added to the connected device
management table 500 of the controller A are the record of the
controller B (record with device ID "004") and the record of the
device B (record with device ID "002") that have newly become
affiliated thereunder. The record of the controller B is the record
added when mutual authentication was performed between the
controller A and controller B in the negotiation processing between
the controller A and controller B (see step S1205 in FIG. 12 and
steps S1410 and S1425 in FIG. 14). The record of the device B is
the record added when device information notified from the old SC
was registered in the SC handover processing from the controller B
(old SC) to the controller A (new SC) (see steps S1320 and S1330 in
FIG. 13).
Comparing FIG. 19B and FIG. 21B, added to the affiliated devices
513 in the group-related information 510 of the controller A are
the device IDs of the controller B and device B that have newly
become affiliated thereunder. This addition has been performed when
registering the devices and old SC notified from the old SC as
affiliated devices thereunder in the SC handover processing from
the controller B (old SC) to the controller A (new SC) (see step
S1320 in FIG. 13).
Comparing FIG. 19C and FIG. 21C, added to the connected device
management table 500 of the controller B is the record of the
controller A (record with device ID "003") that has newly become
the SC. The record of the controller A is the record added when
mutual authentication was performed between the controller A and
controller B in the negotiation processing between the controller A
and controller B (see step S1205 in FIG. 12 and steps S1410 and
S1425 in FIG. 14). Note that the reason why the values of group key
valid time 505 and group key update flag 506 in the connected
device management table 500 of the controller B are shown as "-" in
FIG. 21C is because the controller B is no longer the SC, and
accordingly this is information that does not have to be
managed.
Comparing FIG. 19D and FIG. 21D, the SC 512 in the group-related
information 510 of the controller B has been changed from the
device ID of the controller B to the device ID of the controller A.
This change has been performed when registering the new SC in the
SC handover processing from the controller B (old SC) to the
controller A (new SC) (see step S1325 in FIG. 13). Note that the
reason why the value of affiliated device 513 in the group-related
information 510 of the controller B is shown as "-" in FIG. 21D is
because the controller B is no longer the SC, and accordingly this
is information that does not have to be managed.
Comparing FIGS. 20A and 20B with FIGS. 22A and 22B, there is no
change in the connected controller management table 900 and the
group-related information 910 of the device A. This means that the
group integration this time did not change the SC of the device
A.
Comparing FIGS. 20C and 20D with FIGS. 22C and 22D, the record of
the device ID of the controller A that has newly become the SC is
added to the connected controller management table 900 of the
device B, and the SC 912 of the group-related information 910 is
changed from the device ID of the controller B that is the old SC
to the device ID of the controller A that is the new SC. This
change has been performed when registering the controller A as the
new SC after the device B that was affiliated under the old SC
received the SC change notification from the old SC, in the SC
handover processing from the controller B (old SC) to the
controller A (new SC) (see steps S1315 and S1330 in FIG. 13).
Thus, as illustrated in FIGS. 19A through 22D, the connected device
management tables 500 and group-related information 510 of the
controllers, and the connected controller management tables 900 and
group-related information 910 of the devices, are updated.
Flow for New Controller to Join
Description will be made here regarding a flow starting from a
state where none of controllers and devices in a HAN have been
paired, to where a group is configured by performing the
above-described device registration processing, negotiation
processing, SC handover processing, mutual authentication
processing, shared key calculation processing, group key
distribution/reception processing, and group key updating
processing, and further a new controller has joined the group.
First, assumption will be made that a controller A and device A,
that are not paired with any device or controller, exist within the
HAN. In this state, the SC of the controller A is set to the
controller A, and no SC has been set to the device A.
The device registration processing illustrated in FIG. 10 described
above is performed between the controller A and device A by paring
operations between the controller A and device A by the user. In
this device registration processing, no SC has been set for the
device A, so no negotiation processing is performed, and the
controller A set as the SC of the controller A is notified to the
device A as a new SC (see steps S1010, S1020). The device A now
needs authentication with the SC due to the SC having been newly
registered, and accordingly performs mutual authentication
processing with the controller A that is the SC (see steps S1025,
S1030). This mutual authentication processing between the device A
and controller A will be referred to as first mutual
authentication.
After the first mutual authentication, the device A and controller
A perform group key distribution/reception processing, and a group
key is shared between the device A and controller A (see step
S1035). The group key shared at this time will be referred to as a
first group key.
The device A then joins into affiliation under the controller A,
and a group made up of the device A and controller A is formed (see
step S1040). Thereafter, each time the valid time of the first
group key reaches the predetermined value or lower, the controller
A performs the group key updating processing illustrated in FIGS.
17 and 18, and updates the first group key that is the group key
shared within the group.
Assumption will be made that a controller B, that has not been
paired with any device, is newly connected to the HAN. At this
time, the SC of the controller B is set to controller B.
The device registration processing illustrated in FIG. 11 is
performed between the controller A and controller B, by the user
performing the pairing operations between the controller A and
controller B. In this device registration processing, the SC set to
the controller A and the SC set to the controller B differ, so
negotiation processing occurs between the SC of the controller A
and the SC of the controller B (see steps S1110, S1115). In this
case, the controller A and controller B perform negotiation
processing.
Mutual authentication processing between the controller A and
controller B is performed in the negotiation processing (see step
S1205 in FIG. 12). This mutual authentication processing performed
between the controller A and controller B will be referred to as
second mutual authentication. After the second mutual
authentication, which one of the controller A and controller B is
to be the SC is decided.
When the controller B becomes the SC, SC handover processing from
the controller A to the controller B is performed. In the SC
handover processing, group key distribution/reception processing is
performed where the first group key generated by the controller A
that is the old SC is shared between the controller A that is the
old SC and the controller B that is the new SC (see step S1300 in
FIG. 13). At this time, the controller A, controller B, and device
A share the first group key that is the group key generated by the
controller A, and the controller A, controller B, and device A can
perform encrypted communication using the first group key until the
new SC performs group key updating processing.
When the valid time of the first group key reaches the
predetermined value or lower, the group key updating processing
illustrated in FIGS. 17 and 18 is performed. In the group key
updating processing, the controller B that is the SC generates a
group key. This group key will be referred to as a second group key
(see step S1705 in FIG. 17). The controller B then performs mutual
authentication using shared key and random numbers with each of the
controller A and device A, that are affiliated devices thereunder
(see steps S1800 through S1845 in FIG. 18). This mutual
authentication using the shared key and random numbers will be
referred to as third mutual authentication. The controller B shares
the second group key with the controller A and device A, with which
the third mutual authentication has been successful.
As described above, in a case where the SC is handed over to a
controller that has newly joined the group, and the group key is
updated by the new SC, the first mutual authentication, second
mutual authentication, and third mutual authentication are
performed.
Advantages of First Embodiment
In the first embodiment, a group is formed of a controller and
device, and in a state where there are multiple controllers
included in one group, the multiple controllers perform negotiation
processing. The controllers negotiate using the attributes of the
controllers listed in the public key certificates, and thus can
decide a controller, regarding which states in which the power is
off or the controller is disconnected from the network do not
readily occur, as the SC with priority. Accordingly, in cases where
a new device or controller joins the group, and in cases where
there is need to update the group key, the group key can be quickly
shared within the group.
Also, in the first embodiment, when the SC is changed among
controllers, SC handover processing is performed from the old SC to
the new SC, and the new SC takes over the authentication results
that the old SC had performed with affiliated devices thereunder.
Accordingly, authentication using public key certificates between
the new SC and old SC can be omitted. As a result, the processing
load on devices and controllers can be reduced.
Further, in the first embodiment, when the SC is changed among
controllers, the group key generated by the old SC is transmitted
from the old SC to the new SC. Accordingly, the new SC can use the
group key generated by the old SC to perform encrypted broadcast
communication to affiliated devices under the old SC, using the
group key generated by the old SC, even before a group key
generated by the new SC is distributed.
Modifications
Although the authentication system using the authentication method
according to the present disclosure has been described by way of
embodiment, the following modifications may also be made, and the
present disclosure is not restricted to the authentication system
as described above in the embodiment.
First Modification
The SC handover processing in the first embodiment may be modified
as follows. FIG. 25 is a diagram illustrating a modification of SC
handover processing. The processing of steps S2500, S2505, S2510,
S2520, S2525, and S2535 is the same as processing in steps S1300,
S1305, S1310, S1320, S1325, and S1330 in the SC handover processing
according to the first embodiment, so description thereof will be
omitted.
(S2515) The controller B that is the old SC transmits an activation
instruction for the registration mode to the affiliated devices
thereunder and the controller A that is the new SC.
(S2530) Upon receiving the activation instruction for the
registration mode from the controller B, the controller A and the
affiliated devices under the old SC activate the registration
mode.
(S2535) The controller A sequentially performs device registration
processing with the affiliated devices under the old SC. The device
registration processing is the same as the processing in steps
S1005 through S1065 in FIG. 10, so description will be omitted
here.
In the SC handover processing illustrated in FIG. 25, when the SC
has been changed, an activation instruction for the registration
mode is transmitted from the old SC to the affiliated devices under
the old SC and the new SC, so the new SC and the affiliated devices
under the old SC activate the registration mode. Accordingly,
device registration processing can be performed between the
affiliated devices under the old SC and the new SC even without the
user manually activating the registration mode, improving the ease
of use for the user.
Second Modification
In the SC handover processing according to the first embodiment,
when the old SC notifies the new SC of information of affiliated
devices thereunder, the public key certificates of the affiliated
devices thereunder are also transmitted to the new SC. However, the
present disclosure is not restricted to this, and instead of the
old SC transmitting the public key certificates of each of the
affiliated devices thereunder to the new SC, each of the affiliated
devices that has received the SC changing notification from the old
SC may transmit the public key certificate stored therein to the
new SC. In this case, each of the affiliated devices under the old
SC may encrypt the public key certificate using the group key
generated by the old SC and transmit to the new SC.
Third Modification
Description was made regarding the negotiation processing in the
first embodiment that the classifications according to controller
functions are described as attributes of devices described in the
public key certificates, and the controller to become an SC is
decided according to the classification items ("dedicated device",
"general-purpose device", "application"). However, the negotiation
processing according to the present disclosure is not restricted to
this. For example, version information of communication format or
authentication format may be described as attributes of devices
described in the public key certificates, and the controller to
become an SC may be decided by the controller having a public key
certificate in which is described the newest version No. for the
communication format or authentication format out of the
controllers participating in the negotiation processing being
decided to be the SC. Alternatively, a controller having version
information indicating a greater number of compatible devices or
compatible functions may be decided to be the SC. Accordingly, a
controller having the newest functions, or a controller having a
greater number of compatible devices or compatible functions can be
decided to be the SC.
Also, an arrangement may be made where the greatest number of
devices that can be paired with the controller is described as a
device attribute in the public key certificate, and the controller
that has the largest number out of the controllers participating in
the negotiation processing may be decided to be the SC.
Accordingly, a controller that is capable of pairing with a greater
number of devices can be decided to be the SC.
Also, an arrangement may be made where the type of communication
function (cabled, dedicated wireless, general purpose wireless, and
near-field) that the controller handles is described as a device
attribute in the public key certificate, and the controller to be
the SC is decided by the type. In this case, the priority may be
set for priority to become the SC in the order of "cabled",
"dedicated wireless", "general purpose wireless", and "near-field".
This order is an order by which a controller corresponding to
communication where the probability of being connected to the HAN
is the highest (the frequency of not being connected to the HAN is
low) is more likely to be the SC. Accordingly, a controller which
has a high probability of being connected to the HAN when the SC is
needed, can be decided to be the SC.
Also, an arrangement may be made where the type of power source
(all-time power supply, periodic power supply, short-term power
supply) is described as a device attribute in the public key
certificate, and the controller to be the SC is decided by the
type. In this case, the priority may be set for priority to become
the SC in the order of "all-time power supply", "periodic power
supply", and "short-term power supply". This order is an order by
which a controller where the probability of being operating is the
highest (the frequency of the power being off is low) is more
likely to be the SC. Accordingly, a controller which has a high
probability of being on when the SC is needed, can be decided to be
the SC. Here, an "all-time power supply" device is a device which
needs power to be supplied at all times, such as a dedicated
controller or log collecting device for controlling devices, a
distribution board, a power breaker, a refrigerator, an air
conditioner, a solar power generating device, a battery, a
telephone device, a broadband router, a terminator, and so forth. A
"periodic power supply" is a device such as a television set or
video recording device, an audio device, a room light, and so
forth. A "short-term power supply" device is a device such as a
microwave oven, an electric oven, a washing machine, a vacuum
cleaner, a rice cooker, and so forth.
Also, an arrangement may be made where the mode of usage
(stationary (fixed), stationary (movable), portable, worn) is
described as a device attribute in the public key certificate, and
the controller to be the SC is decided by the form. In this case,
the priority may be set for priority to become the SC in the order
of "stationary (fixed)", "stationary (movable)", "portable", and
"worn". This order is an order by which a controller where the
probability of being moved is the highest is less likely to be the
SC. It is conceivable that the less the device moves, the less the
communication environment will change, and the probability of
communication being cut off is low. Also, it is easier to secure
power for a device that does not move. Accordingly, a controller
that is not easily cut off from communication and a power source
can easily be secured can be decided as being the SC.
Further, instead of deciding the SC according to the device
attribute described in the public key certificate, the SC may be
decided by the state of the device at that time, for example, the
controller that has the greatest number of devices with which it is
paired during the negotiation processing may become the SC.
Accordingly, the number of devices needing re-authentication due to
the SC changing can be reduced. Also, the controller that has been
operating for the least number of hours may be the SC, or the
controller that has the most recent date of manufacture may be the
SC. Accordingly, the possibility that authentication processing
cannot be performed due to SC malfunction can be reduced. Also, the
above standards may be combined to decide the security
coordinator.
Fourth Modification
The negotiation processing according to the first embodiment has
been described as being automatically performed by the controllers.
However, the negotiation processing according to the present
disclosure may be such that the controllers present controllers to
the user as candidates for the SC, and the user selects a
controller to be the SC from the presented candidates. At this
time, all controllers that can be the SC may be presented as
candidates, or may be presented as candidates when there are
multiple controllers selected according to the standards in the
first embodiment or the third modification.
FIG. 26 is a display example at the display unit of a controller
according to the present modification. FIG. 26 shows that there are
two controllers that are SC candidates, with different home
appliances having been registered to each. Also displayed are the
attributes described in the public key certificate of each of the
two controllers (classification according to function of
controller, version information of communication format,
authentication format, etc., date of manufacture, and running
time). The user decides a controller to serve as the SC, in
accordance with the presented information. The user decision is
input here by, for example, touching a picture in the screen of the
decided controller, inputting a number (1 or 2) given to each of
the controllers from an input device, or inputting an
identification symbol (A or B) of the controller from an input
device. Any device can serve as the input device as long as the
intent of the user can be communicated to the controller, and may
be a physical key input device, icons presented on a touch panel, a
device that gives instructions by audio, a device that gives
instructions by gestures, or a device that gives instructions by
line of sight.
Fifth Modification
While the first embodiment performs challenge-response
authentication where random numbers are encrypted and verified
using a shared key in steps S1510 through S1555, this is not
restrictive, and an authentication format described in RFC 5191 may
be used to perform authentication. RFC 5191 is described in IETF:
RFC 5191: Protocol for Carrying Authentication for Network Access
(PANA), Internet Engineering Task Force (IETF), May 2008, and
accordingly will not be described here. Extensible Authentication
Protocol-pre-shared key (EAP-PSK) may be used in RFC 5191 at this
time. Alternatively, the group key may be derived using an extended
master session key (EMSK) derived as the result of EAP-PSK
negotiation. Further, HMAC-SHA2-256 may be used as the key
derivation function.
Sixth Modification
While the first embodiment performs challenge-response
authentication where random numbers are encrypted and verified
using a shared key in steps S1510 through S1555, this is not
restrictive, and an authentication format described in RFC 6347 may
be used to perform authentication. RFC 6347 is described in IETF:
RFC 6347: Datagram Transport Layer Security Version 1.2, Internet
Engineering Task Force (IETF), January 2008, and accordingly will
not be described here.
Seventh Modification
Although an arrangement is described in the embodiment above where,
when a controller newly joins a group, the newly-joining controller
and controllers already existing within the group activate their
registration modes and perform device registration processing, the
present disclosure is not restricted to this. For example, the
following may be performed. When a controller newly joins, the
controller newly joining and a device within the group activate
their registration modes. At this time, the device references the
connected controller management table and transmits information of
the controller set as the SC of the device, to the newly-joining
controller. The controller newly joining receives the information
of the SC, and can join by authentication thereof as the SC. Thus,
even if the group SC is at a remote location away from home,
authentication between the SC and the newly-joining controller can
be performed by an affiliated device under the SC activating the
registration mode.
Eighth Modification
The controller may display electric power consumption of connected
devices, electric power of a battery, amount of power generated by
a solar power generator, and so forth.
Ninth Modification
The controller may be a distribution board installed in the
home.
Tenth Modification
Description has been made in the first embodiment that the
controller which has become the SC manages the group key valid time
and transmits a group key updating notification to the devices in
the group key updating processing. However, an arrangement may be
made where the group key valid time is notified from the controller
which has become the SC to the devices, the devices manage the
group key valid time, and the devices transmit group key updating
notifications to the controller which has become the SC.
Eleventh Modification
Although the first embodiment manages the group key valid time as
remaining time, this is not restrictive, and may be managed as the
time when the group key was generated or the end time of the valid
period of the group key. In a case of managing as the time when the
group key was generated, the length of the valid period of the
group key is separately stored, the current time is compared with a
time obtained by adding the valid period of the group key to the
time when the group key was generated, and whether or not to update
the group key is determined. In a case of managing as the end time
of the valid period of the group key, the current time is compared
with end time of the valid period of the group key, and whether or
not to update the group key is determined.
Twelfth Modification
Although in a case where a device that has not updated the group
key exists in the group key updating processing, a group key
updating notification is transmitted to update the group key in the
first embodiment, in a case where the power of this device is not
on, the group key updating notification may be periodically
transmitted.
Thirteenth Modification
Although in a case where a device that has not updated the group
key exists in the group key updating processing, a group key
updating notification is transmitted to update the group key in the
first embodiment, in a case where this device is being controlled
by a controller with which it is paired, this device may notify of
group key extension time, with group key updating processing being
performed after the extension time elapses.
Fourteenth Modification
Although description is made in the first embodiment that in the SC
handover processing, the shared key is calculated (S1330) between
the new SC and affiliated devices under the old SC after the SC
change notification, this may be performed at any timing as long as
before the group key valid time runs out and group key updating
processing is performed. For example, this may be performed when a
device is not being operated, or may be immediately before the
group key updating processing. Accordingly, the shared key can be
calculated between the controller and devices without placing a
burden on operations of the device.
Fifteenth Modification
Although the controller A determines the SC (steps S1210 through
S1240) during negotiation processing in the first embodiment, this
is not restrictive, and each of the controller A and controller B
may determine the SC.
Sixteenth Modification
The above-described devices specifically are computer systems
configured including a microprocessor, read-only memory (ROM),
random access memory (RAM), hard disk unit, display unit, keyboard,
mouse, or the like. Computer programs are recorded in the RAM or
hard disk unit. The devices achieve their functions by the
microprocessor operating according to the computer programs. A
computer program is configured by combining multiple command codes
indicating commands to a computer.
Seventeenth Modification
Part or all of the components of which the devices described in the
above embodiments are configured may be configured as one system
LSI. A system LSI is a super-multifunctional LSI fabricated with
multiple components integrated on a single chip, and specifically
is a computer system configured including a microprocessor, ROM,
RAM, and so forth. The RAM stores computer programs. The system LSI
achieves its functions by the microprocessor operating according to
the computer programs. The components of which the above-described
devices are configured may each be independently formed as a single
chip, or part or all may be included in a single chip.
While a system LSI has been described, there are different names
according to the degree of integration, such as IC, LSI, super LSI,
and ultra LSI. The way in which the integrated circuit is formed is
not restricted to LSIs, and may be realized by dedicated circuits
or general-purpose processors. A Field Programmable Gate Array
(FPGA) capable of being programmed after manufacturing the LSI, or
a reconfigurable processor of which the connections and settings of
circuit cells within the LSI can be reconfigured, may be used.
Moreover, in the event of the advent of an integrated circuit
technology which would replace LSIs by advance of semiconductor
technology or a separate technology derived therefrom, such a
technology may be used for integration of the functional blocks, as
a matter of course. Application of biotechnology is a
possibility.
Eighteenth Modification
Part or all of the components of which the above-described devices
are configured may be configured as an IC card detachably mountable
to each device, or a standalone module. The IC card or the module
is a computer system configured including a microprocessor, ROM,
RAM, and so forth. The IC card or the module may include the
above-described super-multifunctional LSI. The IC card or the
module achieves its functions by the microprocessor operating
according to the computer program. The IC card or the module may be
tamper-resistant.
Nineteenth Modification
The present invention may be the method described above, may be a
computer program which realizes these methods by a computer, or may
be digital signals made up of the computer program. The present
invention may be the computer program or the digital signals
recorded in a computer-readable recording medium, such as for
example, a flexible disk, hard disk, CD-ROM, MO, DVD, DVD-ROM,
DVD-RAM, BD (Blu-ray (a registered trademark) Disc), semiconductor
memory, or the like. The present disclosure may also be the digital
signals recorded in these recording mediums.
The present disclosure may be an arrangement where the computer
program or the digital signals are transmitted over an electric
communication line, wireless or cable communication line, a network
of which the Internet is representative, data broadcasting, or the
like.
The present disclosure may be a computer system having a
microprocessor and memory, where the memory stores the computer
program, and the microprocessor operates according to the computer
program. This may also be carried out by another independent
computer system, by the program or digital signals being recorded
in the recording medium and being transported, or by the program or
digital signals being transferred over the network or the like.
Twentieth Modification
Forms realized by optionally combining the above-described
embodiment and the above-described modifications are also included
in the scope of the present disclosure.
Supplement
The following supplemental description of the configuration and
advantages of the present disclosure will further be given.
A. An authentication method according to one form of the present
disclosure is an authentication method for a group to which one or
more devices and two or more controllers on a network belong,
wherein at least one controller within the group decides a
coordinator that manages a group key used in common in the group,
from the controllers in the group, in accordance with attributes of
the controllers, and wherein the coordinator generates a group key,
executes mutual authentication with devices and controllers within
the group, and shares the generated group key with devices and
controllers that have succeeded in authentication.
According to this configuration, in a case where multiple
controllers exist in a group on a network, a suitable controller
can be selected as the SC that manages a group key used in common
within the group.
B. An authentication method according to one form of the present
disclosure is an authentication method for a group to which one or
more devices and a first controller on a network belong, wherein
the first controller generates a first group key, executes first
mutual authentication with devices within the group, and shares the
first group key with devices that have succeeded in authentication,
wherein, in a case where a second controller newly joins the group,
at least one controller within the group decides a coordinator that
manages a group key used in common in the group, from the
controllers in the group, in accordance with attributes of the
controllers, wherein the first controller executes second mutual
authentication with the coordinator, and shares the first group key
in a case where the authentication is successful, wherein the
coordinator performs encrypted communication within the group using
the first group key, and wherein the coordinator generates a second
group key, executes third mutual authentication with the devices
and controllers within the group, and updates the group key of the
devices and controllers that have succeeded in authentication to
the second group key.
According to this configuration, in a case where multiple
controllers exist in a group on a network, a suitable controller
can be selected as the SC that manages a group key used in common
within the group. Further, in a case where the SC has been changed,
the controller that has newly become the SC can perform encrypted
broadcast communication to multiple devices in the group, using the
group key received from the controller that was the old SC.
C. In an authentication method according to one form of the present
disclosure, in the authentication method according to the form B,
the first controller transmits authentication information of
devices within the network to the coordinator, wherein the
coordinator executes the third mutual authentication using
authentication information received from the first controller.
According to this configuration, authentication between the new SC
and affiliated devices under the old SC can be simplified. As a
result, the processing load on devices and controllers can be
reduced.
D. In an authentication method according to one form of the present
disclosure, in the authentication method according to the form B,
the devices and controllers within the group have a registration
mode for executing mutual authentication and registering another
party with which the authentication has been successful, wherein,
in a case where the second mutual authentication has been
successful, the first controller transmits an activation
instruction for the registration mode to the coordinator and the
devices within the group, wherein the devices within the group
receive the activation instruction for the registration mode from
the first controller and activate the registration mode, and
wherein the coordinator receives the activation instruction for the
registration mode from the first controller and activates the
registration mode, and executes the third mutual authentication
with the devices that have activate the registration mode.
According to this configuration, affiliated devices under the old
SC and the new SC can be paired without the user manually
activating the registration mode, so ease of use for the user
improves.
E. In an authentication method according to one form of the present
disclosure, in the authentication method according to the forms A
or B, the controllers within the group each store a public key
certificate in which is described one or more attributes of itself,
wherein the controllers within the group perform the decision using
the attributes described in the public key certificates stored in
each.
According to this configuration, a suitable controller can be
selected as the SC by referencing controller attributes described
in public key certificates.
F. In an authentication method according to one form of the present
disclosure, in the authentication method according to the form E,
the attributes described in the public key certificate are one of
dedicated, general-purpose, and application, wherein the attributes
of dedicated indicate that the controller only provides dedicated
functions for a particular object, wherein the attributes of
general-purpose indicate that the controller provides functions for
each a plurality of objects, wherein the attributes of application
indicate that the controller is software that runs on a device
providing functions for each a plurality of objects, wherein a
controller of which the attributes are dedicated becomes a
coordinator with priority over controllers of which the attributes
are general-purpose and application, and wherein a controller of
which the attributes are general-purpose becomes a coordinator with
priority over controllers of which the attributes are
application.
According to this configuration, a controller with fewer power off
and network disconnected states (controller with attributes
"dedicated device" described in public key certificate) is selected
as the SC more readily. Also, a controller with more power off and
network disconnected states (controller with attributes
"application" described in public key certificate) is selected as
the SC less readily.
G. In an authentication method according to one form of the present
disclosure, in the authentication method according to the form E,
the attributes described in the public key certificate are version
information, wherein controllers within the group perform the
decision in accordance with the newness of a version No. indicated
by version information described in the public key certificate
stored in each.
According to this configuration, a controller having the newest
functions can be selected as the SC.
H. In an authentication method according to one form of the present
disclosure, in the authentication method according to the form E,
the attributes described in the public key certificate are version
information, wherein controllers within the group perform the
decision in accordance with a corresponding device count indicated
by version information described in the public key certificate
stored in each.
According to this configuration, a controller having the most
corresponding devices can be selected as the SC.
I. In an authentication method according to one form of the present
disclosure, in the authentication method according to the forms A
or B, the attributes of the controller are accumulated running time
of the controller.
According to this configuration, the probability that
authentication processing cannot be performed due to malfunction of
the SC can be reduced.
J. In an authentication method according to one form of the present
disclosure, in the authentication method according to the forms A
or B, the attributes of the controller are elapsed time from time
of manufacturing of the controller.
According to this configuration, the probability that
authentication processing cannot be performed due to malfunction of
the SC can be reduced.
K. In an authentication method according to one form of the present
disclosure, in the authentication method according to the forms A
or B, the attributes of the controller are the number of devices
paired with the controller.
According to this configuration, the number of devices where
re-authentication becomes necessary due to the SC changing can be
reduced.
L. In an authentication method according to one form of the present
disclosure, in the authentication method according to the forms A
or B, the controllers within the group have a display and operating
unit, wherein the deciding is processing where the controllers in
the group display information indicating attributes of the
controllers on the display, accept user input selecting one
controller from the controllers in the group with regard to the
display from the operating unit, and making the selected controller
to be the coordinator.
According to this configuration, in a case where multiple
controllers exist in a group on a network, a suitable controller
can be selected as the SC.
M. An authentication method according to one form of the present
disclosure is an authentication method for a group to which one or
more devices and one or more controllers including a first
controller on a network belong, wherein the first controller
generates a first group key, executes first mutual authentication
with devices within the group, and shares the first group key with
devices that have succeeded in authentication, wherein, in a case
where a second controller newly joins the group, at least one
controller within the group decides a coordinator that manages a
group key used in common in the group, from controllers including
the one or more controllers and the second controller newly joined
in the group, in accordance with attributes of the controllers,
wherein the first controller executes second mutual authentication
with the coordinator, and shares the first group key with the
coordinator in a case where the authentication is successful,
wherein the coordinator performs encrypted communication within the
group using the first group key, and wherein the coordinator
generates a second group key when valid time of the first group key
is equal to or smaller than a predetermined value, executes third
mutual authentication with the devices and controllers within the
group, and updates the group key of the devices and controllers
that have succeeded in authentication to the second group key.
N. A controller according to one form of the present disclosure is
a controller comprising: a connecting unit; a negotiator; and an
authentication processing unit, wherein the connecting unit
connects to a group to which one or more devices and one or more
other controllers on a network belong, where one controller of the
other controllers generates a first group key, executes first
mutual authentication with devices within the group, and shares the
first group key with devices that have succeeded in authentication,
wherein the negotiator decides a coordinator that manages the group
key used in common in the group, from the controllers in the group,
in accordance with attributes of the controllers, and wherein the
authentication processing unit executes second mutual
authentication with the one controller, receives the first group
key in a case where the authentication is successful, and performs
encrypted communication within the group using the first group key,
and further, in a case where the authentication unit itself is
decided to be the coordinator, generates a second group key when
valid time of the first group key is equal to or smaller than a
predetermined value, receives authentication information of devices
within the group from the one controller, executes third mutual
authentication with devices and controllers within the group using
the received authentication information, and updates the group key
of the devices and controllers that have succeeded in
authentication to the second group key.
O. A controller according to one form of the present disclosure is
a controller comprising: an authentication unit; and a negotiator,
and is a controller within a group to which one or more devices and
one or more controllers on a network belong, wherein the
authentication processing unit generates a first group key,
executes first mutual authentication with devices within the group,
and shares the first group key with devices that have succeeded in
authentication, wherein, in a case where another controller newly
joins the group, the negotiator decides a coordinator that manages
a group key used in common in the group, from controllers including
the one or more controllers and the other controller newly joined
in the group, in accordance with attributes of the controllers,
wherein the authentication processing unit executes second mutual
authentication with the coordinator, and shares the first group key
with the coordinator in a case where the authentication is
successful, transmits authentication information of devices in the
group to the coordinator, performs third mutual authentication with
the coordinator, and in a case where authentication is successful,
receives a second group key generated by the coordinator when valid
time of the first group key is equal to or smaller than a
predetermined value, and updates the group key that is stored to
the second group key.
According to the present disclosure, in a system where multiple
controllers exist within a group configured within a network such
as a HAN or the like, a controller that performs group key
distribution and updating can be suitably decided. The present
disclosure thus is useful as an authentication system or the like
in a system to which various devices and multiple controllers
connect and operate while communicating with each other.
* * * * *